a. Field of Invention
The present invention is an electronic driver (sometimes referred to as a ballast or controller) and lamp system for controlling the power to one or more gas discharge lamps. It is directed to the problems of present ballasts and gas discharge lamps which waste energy through excess heat generation, and which lack control options and which have inherent problems associated with the filaments in standard fluorescent lamps. The present invention driver is able to power one or more gas discharge lamps, such as fluorescent lamps, without standard filaments. The filaments are replaced with unconnected single electrodes. The present invention driver is also able to light LED tubes that may, for example, replace T8 and T5 fluorescent lamps, even at 8 feet in length, for example.
Fluorescent lamps are used extensively throughout office buildings, schools, hospitals, industrial plants for lighting, as plant grow lights for outdoor lighting, and for many other uses. The power to these lamps is controlled by a variety of present available ballasts which have inherent problems. While standard fluorescent lamps with standard ballasts and less sophisticated electronic ballasts offer some benefits over other lighting techniques, such as lower energy use for comparable light output, these ballasts still waste energy through excessive heat generation, they lack the features available with the present invention and the life of the lamp is limited because of failure of the filaments. Standard ballasts use bulky energy wasting transformers to create a high voltage, low frequency signal to excite the lamp filaments creating thermionic emissions. The present invention uses a low voltage, high frequency sensing signal to cause the electrodes to energize. Existing ballasts require specific impedance matching components that are limited to a specific lamp design. The present invention can power a wide range of lamp sizes without modification, as well as different types of lamps or mixtures of different types of lamps. Examples of different types and mixtures include T5, T8, and 0.325 milliamp to 1.5 amp VHO lamps.
Using the present invention, lamps will burn cooler, last longer and produce a brighter light while using less electricity. The present invention also has a more sophisticated level of control then is available from the present state of the art. It can dim the lamps, delay power-up to improve lamp life, sense when a lamp is missing and respond accordingly by reducing power or shutting down completely, and it can be controlled remotely or by a programmable unit. The present system is also able to light its lamps in extremely low temperature because there is no need to heat the filaments or to vaporize the mercury in the fluorescent lamps. In addition, the preferred zeta scan component enables preprogramming to illuminate selected wavelengths and to vary their intensity over time and to even set up sequential selected wave length intensity increases and decreases, as a user may desire, such as with an external or wireless device.
b. Description of Related Prior Art
The following patents are of interest to the present invention technology:
U.S. Pat. No. 5,105,127 discloses a ballast for control of a two-pin fluorescent lamp. However, this device utilizes a complex system of supplying square pulses comprised of a high frequency signal. These “pulses” are then modulated to achieve dimming.
U.S. Pat. No. 5,039,920 also discloses a ballast for control of a two-pin fluorescent lamp. This device utilizes an even more complex system to supply a wave with a “noncontinuous sinusoidal shape” to the lamps. Effectively these lamps see a single cycle of a sine wave followed by a “notch” or dead zone and then another single cycle.
U.S. Pat. No. 4,392,087 discloses a device to power two-pin fluorescent tubes but requires a tuning capacitor and hence can not accept different lamps loads without modification. Further, dimming is accomplished by decreasing voltage.
U.S. Pat. No. 4,876,485 discloses a device which, while used to power standard fluorescent lamps, teaches the ability to power such lamps with an open filament. However, the frequency is fixed and thus cannot be changed to dim the lamps and cannot automatically be adjusted to match the lamp load.
U.S. Pat. No. 5,287,040 to Guy Lestician, the present inventor herein, is directed to an electronic ballast device for the control of gas discharge lamps. The device is comprised of a housing unit with electronic circuitry and related components. The device accepts a.c. power and rectifies it into various low d.c. voltages to power the electronic circuitry, and to one or more high d.c. voltages to supply power for the lamps. Both the low d.c. voltages and the high d.c. voltages can be supplied directly, eliminating the need to rectify a.c. power. The device switches a d.c. voltage such that a high frequency signal is generated. Because of the choice of output transformers matched to the high frequency (about 38 kHz) and the ability to change frequency slightly to achieve proper current, the device can accept various lamp sizes without modification. The ballast can also dim the lamps by increasing the frequency. The device can be remotely controlled.
U.S. Pat. No. 5,323,090 to Guy Lestician, the present inventor herein, is directed to an electronic ballast system including one or more gas discharge lamps which have two unconnected single electrodes each. The system is comprised of a housing unit with electronic circuitry and related components and the lamps. The system accepts a.c. power and rectifies it into various low d.c. voltages to power the electronic circuitry, and to one or more high d.c. voltages to supply power for the lamps. Both the low d.c. voltages and the high d.c. voltages can be supplied directly, eliminating the need to rectify a.c. power. The device switches a d.c. voltage such that a high frequency signal is generated. Because of the choice of output transformers matched to the high frequency (about 38 kHz) and the ability to change frequency slightly to achieve proper current, the device can accept various lamp sizes without modification. The ballast can also dim the lamps by increasing the frequency. The device can be remotely controlled. Because no filaments are used, lamp life is greatly extended.
U.S. Pat. No. 5,612,597 to Wood describes a circuit and method for driving a load such as a gas discharge illumination device from an ac main supply with a high power factor. The circuit includes a pair of electronic switches arranged in a half bridge configuration and a self oscillating driver circuit having two outputs for driving respective ones of the electronic switches, the electronic switches being coupled across a dc bus voltage and having a switched output coupled to the load. The circuit further includes a voltage regulator circuit coupled across the dc bus voltage and coupled to the self oscillating driver circuit, the voltage regulator circuit maintaining the dc bus voltage within a preset range and preventing the dc bus voltage from exceeding the range if the load is removed or becomes an open circuit. The voltage regulator preferably is a boost regulator switching an inductance. The circuit is particularly suitable for driving gas discharge illumination devices, e.g., fluorescent lamps, at a high power factor with minimum instability of the dc bus. U.S. Pat. No. 7,312,582 B2 to Newman et al An electronic ballast for driving at least one lamp comprising a rectifying circuit operatively connectable to an AC line; a current drawing circuit connected across said rectifying circuit; and an inverter circuit connected to said rectifying circuit that supplies a lamp current to said at least one lamp; wherein said current drawing circuit draws current from said AC line when the instantaneous voltage of said AC line nears zero to reduce the total harmonic distortion of the input current drawn by said ballast. U.S. Pat. No. 7,952,293 B2 to Kelly Power describes factor correction and driver circuits and stages. More particularly, power factor correction circuits are described that utilize an auxiliary inductor winding for power regulation. Driver circuits configured for electrical loads such as series arrangements of light emitting diodes are also described. An exemplary embodiment of a driver circuit can implement a comparator and/or a voltage regulator to allow for improved output current uniformity for high-voltage applications and loads, such as series configurations of LEDs. Embodiments of PFC stages and driver stages can be combined for use as a power supply, and may be configured on a common circuit board. Power factor correction and driver circuits can be combined with one or more lighting elements as a lighting apparatus.
U.S. Pat. No. 8,441,210 B2 to Shteynberg et al provides an apparatus, system and method for power conversion to provide power to solid state lighting, and which may be coupled to a first switch, such as a dimmer switch. An exemplary system for power conversion comprises: a switching power supply comprising a second, power switch; solid state lighting coupled to the switching power supply; a voltage sensor; a current sensor; a memory; a first adaptive interface circuit to provide a resistive impedance to the first switch and conduct current from the first switch in a default mode; a second adaptive interface circuit to create a resonant process when the first switch turns on; and a controller to modulate the second adaptive interface circuit when the first switch turns on to provide a current path during the resonant process of the switching power supply.
Thus, while there is extensive prior art in the ballast and gas-based and solid state lamp areas, none teaches an electronic ballast to power and control these lamps in the manner set forth herein. Notwithstanding the prior art, the present invention is neither taught nor rendered obvious thereby.